I'm a GG stan because I feel they can do more than BG.
Although I think BG's are given stronger choreo's overall and they are obviously more popular than GG, however, when you give a good GG a chance to perform at a BG level, they usually kill it, and IMO it looks better than what BG do.
Girls are usually much lighter on their feet, they also have the hair flicks which guys don't have and you know that if a GG can do many other things naturally, although I'm not saying BG can't do those things naturally either.
Also, the entire industry is pretty male-dominated, so supporting and respecting the girls in the right direction will make a huge impact in the future for female idols.
I do highly respect BG, but they are not for me and even in the early days of music (not just in Kpop), I was into GG much more, so I think it's something that's inside me.